This library is implemented through table os
os
os.clock ()
os.date ([format [, time]])
os.difftime (t2, t1)
os.execute ([command])
os.exit ([code])
os.getenv (varname)
os.remove (filename)
os.rename (oldname, newname)
os.setlocale (locale [, category])
os.time ([table])
os.tmpname ()